Inline `{min,max}_value` even in debug builds
I think it is worth to inline `{min,max}_value` even in debug builds.
See this godbolt link: https://godbolt.org/z/-COkVS
Rollup of 7 pull requests
Successful merges:
- #63678 (Improve HRTB error span when -Zno-leak-check is used)
- #64931 (Reword E0392 slightly)
- #64959 (syntax: improve parameter without type suggestions)
- #64975 (Implement Clone::clone_from for LinkedList)
- #64993 (BacktraceStatus: add Eq impl)
- #64998 (Filter out RLS output directories on tidy runs)
- #65010 (Compare `primary` with maximum of `children`s' line num instead of dropping it)
Failed merges:
r? @ghost
BacktraceStatus: add Eq impl
See discussion on #53487.
---
Is adding `Copy` too ambitious? It's a "status", so I don't forsee any non-POD data that might go in there, but it would restrict future variants more than `Eq` does.
Cc: @withoutboats @abonander
Implement Clone::clone_from for LinkedList
See #28481. This represents a substantial speedup when the list sizes are comparable, and shouldn't ever be significantly worse. Technically split_off is doing an unnecessary search, but the code is hopefully cleaner as a result. I'm happy to rework anything that needs to be changed as well!
syntax: improve parameter without type suggestions
Fixes#64252.
This PR improves the suggestions provided when function parameters
do not have types:
- A new suggestion is added for arbitrary self types, which suggests
adding `self: ` before the type.
- Existing suggestions are now provided when a `<` is found where a `:`
was expected (previously only `,` and `)` or trait items), this gives
suggestions in the case where the unnamed parameter type is generic
in a free function.
- The suggestion that a type name be provided (e.g. `fn foo(HashMap<u32>)`
-> `fn foo(HashMap: TypeName<u32>)`) will no longer occur when a `<` was
found instead of `:`.
- The ident will not be used for recovery when a `<` was found instead
of `:`.
r? @Centril
cc @estebank @yoshuawuyts
Reword E0392 slightly
Make it clearer that a type or lifetime argument not being used can be
fixed by referencing it in a struct's fields, not just using `PhathomData`.
CC #53589.
Improve HRTB error span when -Zno-leak-check is used
As described in #57374, NLL currently produces unhelpful higher-ranked
trait bound (HRTB) errors when '-Zno-leak-check' is enabled.
This PR tackles one half of this issue - making the error message point
at the proper span. The error message itself is still the very generic
"higher-ranked subtype error", but this can be improved in a follow-up
PR.
The root cause of the bad spans lies in how NLL attempts to compute the
'blamed' region, for which it will retrieve a span for.
Consider the following code, which (correctly) does not compile:
```rust
let my_val: u8 = 25;
let a: &u8 = &my_val;
let b = a;
let c = b;
let d: &'static u8 = c;
```
This will cause NLL to generate the following subtype constraints:
d :< c
c :< b
b <: a
Since normal Rust lifetimes are covariant, this results in the following
region constraints (I'm using 'd to denote the lifetime of 'd',
'c to denote the lifetime of 'c, etc.):
'c: 'd
'b: 'c
'a: 'b
From this, we can derive that 'a: 'd holds, which implies that 'a: 'static
must hold. However, this is not the case, since 'a refers to 'my_val',
which does not outlive the current function.
When NLL attempts to infer regions for this code, it will see that the
region 'a has grown 'too large' - it will be inferred to outlive
'static, despite the fact that is not declared as outliving 'static
We can find the region responsible, 'd, by starting at the *end* of
the 'constraint chain' we generated above. This works because for normal
(non-higher-ranked) lifetimes, we generally build up a 'chain' of
lifetime constraints *away* from the original variable/lifetime.
That is, our original lifetime 'a is required to outlive progressively
more regions. If it ends up living for too long, we can look at the
'end' of this chain to determine the 'most recent' usage that caused
the lifetime to grow too large.
However, this logic does not work correctly when higher-ranked trait
bounds (HRTBs) come into play. This is because HRTBs have
*contravariance* with respect to their bound regions. For example,
this code snippet compiles:
```rust
let a: for<'a> fn(&'a ()) = |_| {};
let b: fn(&'static ()) = a;
```
Here, we require that 'a' is a subtype of 'b'. Because of
contravariance, we end up with the region constraint 'static: 'a,
*not* 'a: 'static
This means that our 'constraint chains' grow in the opposite direction
of 'normal lifetime' constraint chains. As we introduce subtypes, our
lifetime ends up being outlived by other lifetimes, rather than
outliving other lifetimes. Therefore, starting at the end of the
'constraint chain' will cause us to 'blame' a lifetime close to the original
definition of a variable, instead of close to where the bad lifetime
constraint is introduced.
This PR improves how we select the region to blame for 'too large'
universal lifetimes, when bound lifetimes are involved. If the region
we're checking is a 'placeholder' region (e.g. the region 'a' in
for<'a>, or the implicit region in fn(&())), we start traversing the
constraint chain from the beginning, rather than the end.
There are two (maybe more) different ways we generate region constraints for NLL:
requirements generated from trait queries, and requirements generated
from MIR subtype constraints. While the former always use explicit
placeholder regions, the latter is more tricky. In order to implement
contravariance for HRTBs, TypeRelating replaces placeholder regions with
existential regions. This requires us to keep track of whether or not an
existential region was originally a placeholder region. When we look for
a region to blame, we check if our starting region is either a
placeholder region or is an existential region created from a
placeholder region. If so, we start iterating from the beginning of the
constraint chain, rather than the end.
Rollup of 13 pull requests
Successful merges:
- #64581 (Fix unreachable_code warnings for try{} block ok-wrapped expressions)
- #64850 (Remove inlines from DepNode code)
- #64914 (regression test for 64453 borrow check error.)
- #64922 (Use PlaceBuilder to avoid a lot of slice -> vec -> slice convertions)
- #64948 (Improve sidebar styling to make its integration easier)
- #64961 (Make comment about dummy type a bit more clear)
- #64967 (Don't mark borrows of zero-sized arrays as indirectly mutable)
- #64973 (Fix typo while setting `compile-flags` in test)
- #64980 (Enable support for `IndirectlyMutableLocals` in `rustc_peek` )
- #64989 (Fix ICE #64964)
- #64991 ([const-prop] Correctly handle locals that can't be propagated)
- #64995 (Remove rustdoc warning)
- #64997 (rustc book: nitpick SLP vectorization)
Failed merges:
r? @ghost
Remove rustdoc warning
Removes this warning:
```bash
Finished release [optimized] target(s) in 2.62s
Documenting core v0.0.0 (/home/imperio/rust/rust/src/libcore)
Finished release [optimized] target(s) in 15.23s
Documenting std v0.0.0 (/home/imperio/rust/rust/src/libstd)
Finished release [optimized] target(s) in 17.30s
Documenting proc_macro v0.0.0 (/home/imperio/rust/rust/src/libproc_macro)
Finished release [optimized] target(s) in 2.36s
Documenting test v0.0.0 (/home/imperio/rust/rust/src/libtest)
warning: `[0]` cannot be resolved, ignoring it...
--> src/libtest/lib.rs:1112:41
|
1112 | /// supplied channel. Requires argv[0] to exist and point to the binary
| ^ cannot be resolved, ignoring
|
= note: `#[warn(intra_doc_link_resolution_failure)]` on by default
= help: to escape `[` and `]` characters, just add '\' before them like `\[` or `\]`
Finished release [optimized] target(s) in 1.64s
Build completed successfully in 0:02:07
```
[const-prop] Correctly handle locals that can't be propagated
`const_prop()` now handles writing the Rvalue into the Place in the
stack frame for us. So if we're not supposed to propagate that value,
we need to clear it.
r? @oli-obk
Fixes#64970
Enable support for `IndirectlyMutableLocals` in `rustc_peek`
This PR allows `rustc_peek` tests to be written for the `IndirectlyMutableLocals` analysis implemented in #64470. See any of the tests in [`test/ui/mir-dataflow`](https://github.com/rust-lang/rust/blob/master/src/test/ui/mir-dataflow/inits-1.rs) for an example.
Included in this PR is a major rewrite of the `rustc_peek` module. This was motivated by the differences between the `IndirectlyMutableLocals` analysis and the initialized places ones.
To properly test `IndirectlyMutableLocals`, we must pass locals by-value to `rustc_peek`, since any local that is not `Freeze` will be marked as indirectly mutable as soon as a reference to it is taken. Unfortunately, `UnsafeCell` is not `Copy`, so we can only do one `rustc_peek` on each value with interior mutability inside a test. I'm not sure how to deal with this restriction; perhaps I need to special case borrows preceding a call to `rustc_peek` in the analysis itself?
`rustc_peek` also assumed that the analysis was done on move paths and that its transfer function only needed to be applied at assignment statements. This PR removes both of those restrictions by adding a trait, `RustcPeekAt`, that controls how the peeked at `Place` maps to the current dataflow state and using a dataflow cursor to retrieve the state itself.
Finally, this PR adds a test which demonstrates some unsoundness in the `IndirectlyMutableLocals` analysis by converting a reference to a `Freeze` field to a reference to a `!Freeze` field by offsetting a pointer (or in this case transmuting a pointer to a ZST field with the same address as a `!Freeze` field). This does not represent a hole in the language proper, since this analysis is only used to validate `const` bodies, in which the unsound code will only compile with `-Zunleash-the-miri-inside-of-you`. Nevertheless, this should get fixed.
r? @oli-obk
Fix typo while setting `compile-flags` in test
This test is meant to check for an ICE when generating debug info, but didn't actually pass `-g` due to the typo.
I also removed the `FIXME`, since this needs to actually be built (not just checked) to trigger the ICE.
Improve sidebar styling to make its integration easier
Part of https://github.com/rust-lang/docs.rs/issues/417
Setting the height was an error: forcing the element bottom to be at the bottom allows to change to top of the sidebar.
r? @Mark-Simulacrum
`const_prop()` now handles writing the Rvalue into the Place in the
stack frame for us. So if we're not supported to propagate that value,
we need to clear it.
This commit improves the suggestions provided when function parameters
do not have types:
- A new suggestion is added for arbitrary self types, which suggests
adding `self: ` before the type.
- Existing suggestions are now provided when a `<` is found where a `:`
was expected (previously only `,` and `)` or trait items), this gives
suggestions in the case where the unnamed parameter type is generic
in a free function.
- The suggestion that a type name be provided (e.g. `fn foo(HashMap<u32>)`
-> `fn foo(HashMap: TypeName<u32>)`) will no longer occur when a `<` was
found instead of `:`.
- The ident will not be used for recovery when a `<` was found instead
of `:`.
Signed-off-by: David Wood <david@davidtw.co>
Update books
## reference
3 commits in fa5dfb832ef8a7568e17dabf612f486d641ff4ac..320d232b206edecb67489316f71a14e31dbc6c08
2019-09-16 20:42:56 +0200 to 2019-10-01 17:05:35 +0200
- Update async/await keywords to real keywords. (rust-lang-nursery/reference#687)
- Remove the warning that appears on every page. (rust-lang-nursery/reference#685)
- Eschew fp lit pattern (rust-lang-nursery/reference#683)
## book
9 commits in 871416b85c1a73717d65d6f4a9ea29e5aef3db0e..04806c80be0f54b1290287e3f85e84bdfc0b6ec7
2019-09-16 09:46:20 -0400 to 2019-10-01 20:20:22 -0400
- Fix tidy error. (rust-lang/book#2104)
- Fancy quotes
- Commit autogenerated cargo content
- Move all scripts into tools
- We can start lines with numbers without creating ordered lists
- ci: validate that all used references are defined (rust-lang/book#2032)
- Remove the check for unstable features
- Specify the rustc version we're using in a rust-toolchain file
- Fix broken link to Chapter 13-01 in Chapter 12-04 (rust-lang/book#2025)
## rust-by-example
9 commits in 67cfbf31df880728dcf7cb35b15b028ec92caf31..a6288e7407a6c4c19ea29de6d43f40c803883f21
2019-09-18 09:36:40 -0300 to 2019-10-01 10:09:14 -0300
- Add reference to lifetime in structs (rust-lang/rust-by-example#1274)
- Rectangle ambiguity (rust-lang/rust-by-example#1270)
- Make Parsing a String code editable (rust-lang/rust-by-example#1268)
- Fix match range pattern usage (rust-lang/rust-by-example#1269)
- Added type alias enum variant rfc (rust-lang/rust-by-example#1267)
- Chapter 9.2.5: impl FnOnce() works in 1.35 (rust-lang/rust-by-example#1266)
- Move chapters from folder "traits" to "trait" (rust-lang/rust-by-example#1263)
- Capturing changes (rust-lang/rust-by-example#1265)
- Fixrust-lang/rust-by-example#1261: document Iterator::position (rust-lang/rust-by-example#1262)
r? @ghost
Fully clear `HandlerInner` in `Handler::reset_err_count`
Address [`FIXME`](702b45e409/src/librustc_errors/lib.rs (L472)) for `Handler::reset_err_count` in the way suggested by @Mark-Simulacrum, i. e. clear all the fields of `HandlerInner`.
cc @estebank
Fix zebra-striping in generic dataflow visualization
A small formatting improvement to #64828.
Prior to this, the background color of the first row of the table for each basic block changed seemingly at random. You can see this in [basic block #5](https://github.com/rust-lang/rust/pull/64828#issuecomment-536690047) under "New table". Now it is always light.
This also updates the example table to match the current output.
use try_fold instead of try_for_each to reduce compile time
as it was stated in #64572 that the biggest gain was due to less code was generated I tried to reduce the number of functions to inline by using try_fold direct instead of calling try_for_each that calls try_fold.
as there is some gains with using the try_fold function this is maybe a way forward.
when I tried to compile the clap-rs benchmark I get times gains only some % from #64572
there is more function that use eg. fold that calls try_fold that also can be changed but the question is how mush "duplication" that is tolerated in std to give faster compile times
can someone start a perf run?
cc @nnethercote @scottmcm @bluss
r? @ghost
SelfProfiler API refactoring and part one of event review
This PR refactors the `SelfProfiler` a little bit so that most profiling methods are RAII-based. The codegen backend code already had something similar, this refactoring pulls this functionality up into `SelfProfiler` itself, for general use.
The second commit of this PR is a review and update of the existing events we are already recording. Names have been made more consistent. CGU names have been removed from event names. They will be added back in when function parameter recording is implemented.
There is still some work to be done for adding new events, especially around trait resolution and the incremental system.
r? @wesleywiser
